1. Field of the Invention
This invention relates to automatic actuators commonly used in conjunction with inflators for inflating articles such as personal flotation devices, rafts, buoys and emergency signalling equipment. More particularly, this invention relates to electrically actuated squib assemblies designed to pierce the frangible seal of a compressed gas cartridge allowing compressed gas therein to inflate the inflatable article.
2. Description of the Background Art
Presently, there exist many types of inflators designed to inflate inflatable articles such as personal flotation devices (life vests, rings and horseshoes), life rafts, sonobuoys and emergency signaling equipment. These inflators typically comprise a body for receiving the neck of a cartridge of compressed gas such as carbon dioxide. A reciprocating pierce pin is disposed within the body for piercing the frangible seal of the cartridge to permit the compressed gas therein to flow into a manifold in the body and then into the device to be inflated. Typically, a manually movable firing lever is operatively connected to the piercing pin such that the piercing pin pierces the frangible seal of the cartridge upon jerking of a ball lanyard. U.S. Pat. No. 3,809,288, the disclosure of which is hereby incorporated by reference herein, illustrates one particular embodiment of a manual inflator.
While these manual inflators work suitably well, it was quickly learned that in an emergency situation, the person needing the assistance of the inflatable device, such as a downed aviator, injured person, or a man overboard, would fail or be unable to manually actuate the inflator. Accordingly, it was realized that a means should be provided for automatically actuating the inflator in such an emergency situation.
In response to this need, water activated automatic inflators have been developed which, when exposed to a fluid such as water, automatically actuate the piercing pin of the inflator causing inflation of the inflatable device.
One type of water activated automatic inflators comprises a water activated trigger assembly including a water dissolvable element which retains a spring-loaded actuator pin in a cocked position in alignment with the pierce pin, either directly or indirectly by means of an intermediate transfer pin. Upon exposure to water, the element dissolves allowing firing of the cocked actuator pin. The actuator pin then strikes the pierce pin to fracture the seal of the cartridge thereby allowing the gas contained therein to flow into the inflatable device to inflate the same. U.S. Pat. Nos. 3,997,079, 4,223,805 4,267,944, 4,260,075 and 4,627,823 the disclosures of each of which are hereby incorporated by reference herein, illustrate several examples of water activated automatic inflators which employ a dissolvable element.
While the above automatic inflators work quite well to automatically inflate the inflatable device in the event of an emergency situation, one major disadvantage to these automatic inflators is their tendency to self-actuate while stored for subsequent exigent use. Specifically, it is quite common for the automatic inflator to be stored in a highly humid environment such as on a ship or a boat. Over a period of time, the moisture contained within the humid air is absorbed by the water dissolvable element to such a degree that the element is weakened, particularly since the element is continually subjected to the force of the actuator spring. As the element gradually weakens, the strength of the element eventually becomes insufficient to retain the spring-loaded actuator pin in the cocked position. When the element collapses under the force of the compressed spring of the actuator pin, the actuator pin strikes the piercing pin causing premature and unintentional inflation of the inflatable device.
The problem of premature and unintentional actuation of the automatic inflator is so acute that it is not uncommon for a weakened water destructible or dissolvable element to be replaced with a new element on a periodic basis pursuant to a regularly scheduled maintenance plan. In this regard, it is noted that each of the prior art water activated automatic inflators disclosed in the above referenced patents teach a structure which may easily be disassembled to facilitate removal of a weakened element and the installation of a new one. Indeed, U.S. Pat. No. 4,627,823 discloses a safety-latched automatic actuator designed to relieve the pressure exerted on the water dissolvable element until such time as an emergency situation exists.
Another type of water activated automatic inflators comprises a water activated, squib powered inflator. As the term is commonly used, a squib is a self-contained explosive charge. Upon actuation by electric current, the explosive charge explodes and which then actuates the inflator. U.S. Pat. Nos. 3,059,814, 3,091,782, 3,426,942, 3,579,964, 3,702,014, 3,757,371, 3,910,457, 4,382,231, 4,436,159 and 4,513,248, the disclosures of each of which are incorporated by reference herein, illustrate several examples of water activated squib-powered inflators.
While many of the squib-powered inflators disclosed in the above-listed patents suffice for many applications, there exists a need for an inflator adaptor which is compact in design facilitating use of the inflator in a variety of inflation devices. There also exists a need for an inflator adaptor which is simple in construction so as to reduce manufacturing costs. Specifically, there exists a need for an economical and reliable squib-powered inflator used to inflate a sonobuoy. In this regard, a sonobuoy typically comprises an inflatable device which is dropped from an aircraft into a body of water; the device including appropriate electronics to detect submarines and transmit such information to the aircraft overhead. It is believed that such squib-powered inflators have been developed in Europe prior to the invention hereof; however, no specific disclosure of such inflators is known to me other than the brochure attached to the Information Disclosure Statement filed concurrently herewith.
Therefore, an object of this invention is to provide an inflator adaptor having a compact design allowing it to be easily incorporated in a variety of inflation devices.
Another object of this invention is to provide an inflator adaptor having a simple design which is economical to manufacture.
The foregoing has outlined two of the more pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.